摘要:
The present invention provides a semiconductor memory device including: a semiconductor substrate of a first conductivity type; and a memory cell including: (i) a columnar semiconductor portion formed on the substrate, (ii) at least two charge-storage layers formed around a periphery of the columnar semiconductor portion and divided in a direction vertical to the semiconductor substrate, and (iii) a control gate that covers at least a portion of charge-storage layers, wherein the memory cell is capable of holding two-bit or more data.
摘要:
An etching method for a semiconductor device comprising the steps of: generating an etching species atmosphere above the semiconductor device having a step composed of a main surface and a sidewall; and applying an electric field to accelerate the etching species in one direction and a magnetic field along a plane that crosses the one direction at a specific angle so that the sidewall is etched.
摘要:
A semiconductor device, which is characterized by that two or more island-shaped semiconductor layers including first and second island-shaped semiconductor layers are formed on the same substrate, at least the first island-shaped semiconductor layer has steps in its side wall so that sectional area of a cross section parallel to the surface of the substrate varies stepwise with respect to height in the vertical direction, the second island-shaped semiconductor layer is different from the first island-shaped semiconductor layer with respect to the presence/absence of a step in the side wall or the number of steps, and each of the first and second island-shaped semiconductor layers provides an element on a stair part of the side wall divided by the steps or on the side wall having no steps.
摘要:
An ion implantation method for implanting ions into a side wall of a protruded semiconductor layer from a semiconductor substrate, the method includes applying an electric field to accelerate the ions in one direction and applying a magnetic field parallel to a plane extending at a predetermined angle with respect to the one direction, thereby controlling a direction of the ion implantation to the side wall.
摘要:
A semiconductor device, which is characterized by that two or more island-shaped semiconductor layers including first and second island-shaped semiconductor layers are formed on the same substrate, at least the first island-shaped semiconductor layer has steps in its side wall so that sectional area of a cross section parallel to the surface of the substrate varies stepwise with respect to height in the vertical direction, the second island-shaped semiconductor layer is different from the first island-shaped semiconductor layer with respect to the presence/absence of a step in the side wall or the number of steps, and each of the first and second island-shaped semiconductor layers provides an element on a stair part of the side wall divided by the steps or on the side wall having no steps.
摘要:
An ion implantation method for implanting ions into a side wall of a protruded semiconductor layer from a semiconductor substrate, the method includes applying an electric field to accelerate the ions in one direction and applying a magnetic field parallel to a plane extending at a predetermined angle with respect to the one direction, thereby controlling a direction of the ion implantation to the side wall.
摘要:
The present invention provides a semiconductor memory device including: a semiconductor substrate of a first conductivity type; and a memory cell including: (i) a columnar semiconductor portion formed on the substrate, (ii) at least two charge-storage layers formed around a periphery of the columnar semiconductor portion and divided in a direction vertical to the semiconductor substrate, and (iii) a control gate that covers at least a portion of charge-storage layers, wherein the memory cell is capable of holding two-bit or more data.
摘要:
A semiconductor memory device comprises a memory array on a semiconductor substrate having a constitution such that a plurality of memory cells where one end of the variable resistive element is connected to either an emitter or a collector of a bipolar transistor are arranged in the row and the column directions in a matrix form, the other of the emitter or the collector of the bipolar transistor in each memory cell in the same column is connected to common source line extending in the column direction, a base of the bipolar transistor in each memory cell in the same row is connected to common word line extending in the row direction, the other end of the variable resistive element in each memory cell in the same column is connected to common bit line extending in the column direction.
摘要:
A method for efficiently amplifying abnormal prion protein (PrPSc) derived from bovine spongiform encephalopathy (BSE) is provided. Ultimately, the invention aims at eradicating the transmission of a prion disease by detecting a BSE-infected cow early and developing a method for inactivating prions and permitting early examination of prion inactivation. Provided is a method for efficiently amplifying PrPSc derived from BSE, wherein the method is based on a PMCA (protein misfolding cyclic amplification) method in which normal prion protein (PrPC) is used as a source and PrPSc is used as a seed, and PrPSc derived from BSE is amplified by stir-mixing, incubating, and sonicating both the PrPC and the PrPSc repeatedly, and wherein the method includes performing stir-mixing-incubation-sonication in the presence of a polysaccharide sulfate.